[@rollup/plugin-esm-shim] Shim inserted incorrectly if source file has import in comment

[EvanHahn]

• Rollup Plugin Name: @rollup/plugin-esm-shim
• Rollup Plugin Version: 0.1.6
• Rollup Version: 4.13.3
• Operating System (or Browser): Linux (Debian Bookworm)
• Node Version: v20.12.2
• Link to reproduction: https://gist.github.com/EvanHahn/d8a353ef88376072371a1b8a02876e7d

Expected Behavior

The shim should be inserted in the right place, even if the source file contains static imports in comments.

For example, the shim should be inserted right after the import in the file below:

import foo from "./other_module.js";

// Triggers the shim
require();

/*
import BAD from "./bad";
*/

Actual Behavior

The shim is inserted in a strange place, causing syntax errors.

Additional Information

I believe this bug happens because the plugin tries to insert the shim after the last import, but incorrectly detects them when they're inside comments.

imports are detected with the following regular expression:

plugins/packages/esm-shim/src/constants.ts

Lines 13 to 14 in 9e7f576

	export const ESMStaticImportRegex =
	/(?<=\s|^|;)import\s*([\s"']*(?<imports>[\w\t\n\r $*,/{}]+)from\s*)?["']\s*(?<specifier>(?<="\s*)[^"\n]*[^\s"](?=\s*")|(?<='\s*)[^'\n]*[^\s'](?=\s*'))\s*["'][\s;]*/gm;

This expression is unaware of comments.

I would probably solve this by parsing the AST rather than using a regular expression. Let me know if you'd like me to make that pull request.